Interface apparatus for stimulation of biological tissue

ABSTRACT

An apparatus for interfacing between tissues being stimulated is provided. The apparatus includes an electric source capable of generating an applied electric field across a region of tissue and/or a means for altering at least one electromagnetic characteristic of the region of tissue relative to the applied electric field and an interface component, such interface component creating an interface between the region of tissue and the applied electric field or the means for altering at least one electromagnetic characteristic of the region of tissue.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims priority to U.S. Provisional ApplicationSer. No. 61/086,989 filed in the U.S. Patent and Trademark Office onAug. 7, 2008 by Wagner, and is a continuation-in-part of U.S.application Ser. No. 11/764,468, filed in the U.S. Patent and TrademarkOffice on Jun. 18, 2007 by Wagner et al., which claims priority to U.S.Provisional Application Ser. No. 60/814,843, filed in the U.S. Patentand Trademark Office on Jun. 19, 2006, the entire contents of which areincorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION

A. Field of the Invention

The present disclosure relates generally to the field of altering and/orgenerating currents in biological tissue for the purpose of stimulation.More particularly, the present disclosure relates to an apparatus thatserves as an interface mechanism between tissue being stimulated and/oran electrical field (and/or electric field source) and/or a means foraltering the tissue electromagnetic parameters (fields, agents, and/orsources).

B. Background Information

Electric stimulation of living tissue in humans and other animals isused in a number of clinical applications as well as in generalbiological research. In particular, electric stimulation of neuraltissue has been used in the treatment of various diseases includingParkinson's disease, depression, and intractable pain. Focused and/ordeep stimulation of the brain usually involves performing surgery toremove a portion of the skull and implanting electrodes in a specificlocation within the brain tissue. The invasive nature of theseprocedures makes them difficult and costly, and is responsible for agreat deal of morbidity. Alternately, noninvasive stimulationmethodologies such as transcranial direct current stimulation (tDCS) andtranscranial magnetic stimulation (TMS) are easy to implement and arenot associated with significant morbidity, however, the areas stimulatedare large, typically not well characterized, and can be significantlyperturbed by natural or pathological features of the brain tissue.Recently, ultrasound stimulation of brain tissue has been explored withlimited success, as it alone does not generate currents that are thebackbone of clinically effective stimulation methods.

Numerous methods exist for generating currents for biological tissuestimulation. These methods range from implanting electric sources in thetissue to inductively generating currents in tissue via time-varyingmagnetic fields. A new method for generating currents in biologicaltissue was recently described in U.S. patent application Ser. No.11/764,468, Apparatus and Method for Stimulation of Biological Tissue,which discloses an apparatus and method of generating currents inbiological tissues. The disclosure describes a means to stimulatebiological tissue via an electric source capable of generating anelectric field across a region of tissue and a means for altering theelectromagnetic properties of tissue relative to the electric field,whereby the alteration of the tissue electromagnetic properties relativeto the electric field generates an altered current in the tissue. Thesealterations in the current in turn lead to the stimulation of biologicaltissue. The means for altering these electromagnetic parameters of thetissue could include a chemical, optical, mechanical, thermal, and/orsecondary electromagnetic source(s), field(s), and/or agents.

Presently, no apparatus exists which can improve on the interfacebetween the primary electric source (and/or field) and/or means to altertissue electromagnetic properties (source(s), field(s), and/or agents)and/or the tissue(s) to be stimulated for this type of tissuestimulation method. No interface exists which can regulate the number ofand/or duration of stimulation sessions. No interface exists which cancontrol, move, and/or fix the location and/or sizes of the source of theprimary electric field and/or means for altering the electromagneticproperties of the tissue(s) to be stimulated for this type of tissuestimulation method. No interface exists Which specifically bridges,couples, and/or matches the properties of the materials between theprimary electrical field source (and/or its field) and/or the source ofthe means for altering these electromagnetic parameters of the tissue(and/or the fields and/or agents) and/or the tissue in such a way toimprove stimulation for this type of tissue stimulation method. Nointerface has been proposed which can be worn, integrated with wearableitems, house any of the sources of stimulation, and/or serve as a bridgebetween tissue(s) to be stimulated and any of the sources ofstimulation.

It would be desirable to provide an interface mechanism between thestimulated tissue and/or the source electrical field(s) and/or the meansfor altering the tissue's electromagnetic characteristics that makessuch improvements. The present disclosure addresses these deficiencies.

II. SUMMARY OF THE INVENTION

Accordingly, an interface apparatus is presented. The interfaceapparatus could be used to regulate the number of stimulation sessions(and/or duration of stimulation), house the electrical field sourceand/or the source of the means for altering the tissue's electromagneticcharacteristics, and/or act as a bridging medium between the tissueand/or the electric field (and/or source) and/or the means for alteringthe tissues electromagnetic properties (source(s), field(s), and/oragents). The interface apparatus according to the present disclosure caninclude an electric source capable of generating an applied electricfield across a region of tissue, a means for altering at least oneelectromagnetic characteristic of the region of tissue relative to theapplied electric field, and an interface component, such interfacecomponent creating an interface between the region of tissue and appliedelectric field and/or the means for altering at least oneelectromagnetic characteristic of the region of tissue. It is envisionedthat according to the present disclosure, the characteristics of tissuecan be altered using a variety of sources including, but not limited to,a chemical source, optical source, mechanical source, thermal source,and/or a secondary electromagnetic source (and/or the source generatedfield(s) and/or agents).

According to the current disclosure, the tissue permittivity can bealtered relative to an applied electric field. The alteration thengenerates a displacement current in the region of tissue. Furtherconductivity can be altered relative to an applied electric fieldthereby generating an altered ohmic current. The alteration of anelectromagnetic characteristic of a region of tissue can also be used togenerate a new electric field that has the ability to drive additionalohmic and displacement currents.

The interface apparatus can include either a separate piece that is awearable component (such as for example a helmet that could be worn bythe person being stimulated in the brain); an external wrap(s) (ofvarious shapes tailored for any part of the body) or wearable items;bridging blocks; electrode like components; transducer like components;materials that can be worn and/or integrated into other wearable items;a physical boundary component of the headpiece of a transducer mechanismfor the field(s) and/or electromagnetic tissue parameter(s) modifier(s);any physical boundary component which directs or couples at least one ofthe sources, fields, agents, or means for altering tissueelectromagnetic properties with the tissue; and/or any combination ofthe above.

The interface apparatus may have its number of uses regulated (and/orthe duration of stimulation) through multiple methods including use ofan integrated electrical circuit, which can control the number of uses(or time) through which the interface component may be used (which maybe controlled for example through electrical or mechanical interfaces,memory devices, card readers, telecommunication devices, etc); use ofinterface creams, pastes, fluids, materials, and/or gels which can befashioned to be only functional for a single use (or a controlled numberof uses and/or duration of stimulation); use of mechanical safetylatches which deactivates the item after a single use (or a controllednumber of uses and/or duration of stimulation); and/or use of acomposite material which makes up part of the apparatus according to thepresent disclosure and can regulate the number of applications and/orduration of stimulation; and/or other standard mechanisms (all usedindividually or in any combination).

The interface apparatus according to the present disclosure could beused to match and/or appropriately couple the physical characteristicsbetween the tissue(s) and/or the electrical field (or electric fieldsource) and/or means for altering the tissue electromagnetic parametersto augment, focus, modify, and/or improve the current alteration. Theinterface could also be used to adjust the position, shape, and/or sizeof the components of the stimulation method that can be housed in theinterface and/or in contact with the interface relative to the tissue tobe stimulated.

III. BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other features and objects of this invention,and the manner of attaining them, will become more apparent and theinvention itself will be better understood by reference to the followingdescription of embodiments of the invention taken in conjunction withthe accompanying drawings, wherein:

FIG. 1 is a plan view of an exemplary embodiment of an interfaceapparatus in accordance with the present disclosure;

FIG. 2 is a plan view of an another exemplary embodiment of an interfaceapparatus in accordance with the present disclosure; and

FIG. 3 is a plan view of an interface apparatus in accordance with thepresent disclosure.

IV. DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

It is envisioned that the present disclosure may be used as a method toaugment or use in connection with the stimulation of biological tissuethrough the methods described in U.S. patent application Ser. No.11/764,468, Apparatus and Method for Stimulation of Biological Tissue,where an electric source that is placed on the body to generate anelectric field is combined with a means for altering the electromagneticproperties of the tissue relative to the electric field, whereby thealteration of the tissue electromagnetic properties relative to theelectric field generates an altered current in the tissues.

As provided by the present disclosure, an interface apparatus isintroduced. The interface apparatus according to the present disclosurecan be used between stimulated tissue and/or the primary electric field(or electric field source) and/or the means for altering theelectromagnetic tissue parameters (i.e., the ultrasound/mechanical fieldand/or source(s), chemical agent and/or source(s), thermal field and/orsource(s), optical field/beam and/or source(s), and/or secondaryelectromagnetic field and/or source(s)). The exemplary embodiments ofthe apparatus disclosed can be employed in the area of neuralstimulation and muscular stimulation (including cardiac stimulation). Itis also envisioned that the present disclosure may also be employed inthe area of cellular metabolism, physical therapy, drug delivery, andgene therapy.

A detailed embodiment of the present disclosure is presented herein,however, it is to be understood that the described embodiments aremerely exemplary of the disclosure, which may be embodied in variousforms. Therefore, specific functional details disclosed herein are notto he interpreted as limiting, but merely as a basis for the claims andas a representative basis for teaching one skilled in the art tovariously employ the present disclosure in virtually any appropriatelydetailed embodiment.

The components of the tissue stimulation interface apparatus accordingto the present disclosure are fabricated from materials suitable for avariety of medical applications, such as, for example, polymerics, gels,films, fabrics, and/or metals, depending on the particular applicationand/or preference. Semi-rigid and rigid polymerics are contemplated forfabrication, as well as resilient materials, such as molded medicalgrade polyurethane, as well as flexible or malleable materials, such asfabrics, flexible polymerics, or materials for wearable items. Themotors, gearing, electronics, power components, electrodes, andtransducers of the apparatus may be fabricated from those suitable for avariety of medical applications. The interface apparatus according tothe present disclosure may also be used in connection with or includecircuit boards, circuitry, processor components, etc. for computerizedcontrol. One skilled in the art, however, will realize that othermaterials and fabrication methods suitable for assembly and manufacture,in accordance with the present disclosure, also would be appropriate.

The following discussion includes a description of the components andexemplary methods for creating an interface between tissue and/or anelectric field (and/or electric field source) and/or means for alteringthe electromagnetic tissue parameters (source(s), field(s), and/oragents). Reference will now be made in detail to the exemplaryembodiments of the present disclosure illustrated in the accompanyingfigure wherein like reference numerals indicate the similar partsthroughout the figure.

Turning now to FIG. 1, which illustrates an exemplary embodiment of aninterface apparatus 8. An interface component 10 can be used to providean interface between the tissue, and the electric field (and source),and means for altering the electromagnetic tissue properties. Forexample, the interface apparatus 8 illustrated in FIG. 1 according tothe present disclosure may be applied to the area of neural stimulation(and in particular brain stimulation).

Electrodes 12, as an electric source, are applied to the scalp throughinterface component 10. As depicted in FIG. 1, interface component 10,can be a cap, helmet, or other item that can be worn by an individual.Further, it is envisioned that electrodes 12 can be separate or attachedto, embedded in, placed on top of, placed on the surface of or fastenedwithin (or any combination to) the interface component 10. The capinterface component 10 can serve as an interface between regions oftissue of an individual and electrodes (or as a holder for theelectrodes directly affixed to the skin with an area opened on theinterface mechanism). While electrodes 12 are used and applied to thescalp through the interface mechanism in this exemplary embodiment, itis envisioned that the electrodes may be applied to a number ofdifferent areas on, within, or near the body including areas around thescalp through a single interface component, multiple interfacecomponents, and/or a combination of an interface component(s). Theelectrodes used may or may not be housed in an interface component ofthe interface apparatus according to the present disclosure. By way ofexample, the main electrode(s) used could be housed within an interfacecomponent affixed to the scalp and a free electrode could be placed inthe subject's mouth. It is also envisioned that one electrode may heplaced proximal to the tissue being stimulated and the other distant,such as one electrode on the scalp and one on the thorax (through asingle interface component (containing at least one of the electrodeelements, where the other electrodes may be housed in an interfacecomponent and/or as separate non-interface component-containedelectrodes), and/or through multiple interface components).

It is further envisioned that the electric source could be mono-polarwith a single electrode (where a cap interface component could serve asthe entire or part of the electrode), or multi-polar with multipleelectrodes where at least one of the electrodes is contained (or partof) in at least one interface component. Similarly, the electric sourceof the interface apparatus (and/or the interface component) may beapplied to tissue via any medically acceptable medium (i.e., gels,creams, pastes, fluids, dry application electrodes, etc). By using dryelectrodes (and/or a dry interface component), one could potentiallyeliminate the debris left on the subject following stimulation. It isalso envisioned that the electric source could generate its field viainductive means whereby a magnetic source is embedded in the capinterface component. The interface component can itself be comprised ofinert and/or active materials that serve as a bridging medium andappropriately couple and/or match the electromagnetic characteristicsbetween an electrical source and a region or regions of tissue (forexample, by actively or passively altering and/or matching theelectrical impedances between the tissues and the electric source(s)).Finally the interface component(s) themselves(s) may serve as anelectric source(s) itself, in whole or part.

The electrodes generate a source electric field 14, which results in acurrent in the tissue. As described in further detail below, theelectromagnetic properties of the tissue are altered relative to theelectric field, for example by a mechanical field, thereby generating anew and altered current component relative to the initial field and/oran additional new electrical field component, including ohmic and/ordisplacement current components.

As further depicted in FIG. 1, a mechanical source (the mechanicalsource may be any acoustic source such as an ultrasound device) 16 isapplied on the scalp via interface mechanism 10 and providesconcentrated acoustic energy 18 (i.e., mechanical field) to a focusedregion of neural tissue in the brain of a subject. This mechanical field18 affects a smaller number of neurons 22 than is affected by theelectric field 14 and thereby generates the altered current 24. A blockof tissue 20, is depicted in a magnified view with neurons 22 to bestimulated in FIG. 1.

The mechanical source 16 and subsequent field 18 can be applied to thescalp through the interface mechanism 10, which can be a cap, helmet, orwearable item as depicted in FIG. 1. It is envisioned that themechanical source can be attached to, embedded in, placed on top of,placed on the surface of, or fastened within (or any combination to) theinterface component 10 of interface apparatus 8. Thus, the interfacecomponent 10 can serve as an interface between the region of tissue ortissues and mechanical source (or as a holder for the mechanical sourcein direct contact with the tissue). Multiple mechanical sources could beapplied (through either one interface mechanism (with multiplemechanical sources), multiple interface mechanisms (containing orinterfacing with at least one mechanical source), or through any suchcombination (and/or with separate non-interface component-containedmechanical sources)).

While a mechanical source 16 can be used and applied to the scalpthrough interface component 10 as depicted in this exemplary embodiment,it is envisioned that mechanical source(s) may be applied to a number ofdifferent areas on, within, or near the body including areas around thescalp through a single interface component, multiple interfacecomponents, and/or a combination of an interface component(s) and/ormechanical sources that are not housed in an interface component.Similarly, the mechanical source component of the interface apparatus(and/or the interface component) may be applied to tissue via anymedically acceptable medium (i.e., gels, creams, fluids, pastes, etc).The interface component itself can be comprised of materials, activeand/or inert, that serve as a bridging medium, thus creating theinterface, and thereby appropriately coupling and/or matching themechanical properties between the mechanical source and the targetedtissues (for example, by actively and/or passively matching and/oraltering the acoustic impedances between the tissues and the electricsource(s)). The interface component itself may serve as a mechanicalsource(s) itself, in whole or part.

As the electric field is to be coupled to the mechanical field, theinterface component itself can be comprised of materials, active and/orinert, that serve as a bridging medium, thus creating an interface, andthereby appropriately couple and/or match the acoustic characteristicsand/or electromagnetic properties between the mechanical source and/orfields (or other means for altering electromagnetic characteristics)and/or the electric source and/or fields and/or the tissues to augmentthe stimulation. This can be done for example, by having the interfacecomponent at least in part capable of: actively and/or passivelymatching and/or altering the electrical and acoustic impedances of theinterface to the electrical and mechanical field frequencies that aretuned to initiate stimulation of neural cells, and/or actively and/orpassively matching and/or altering the electrical and acousticimpedances of the interface to the sources such that the sourcesthemselves are matched and more efficient in use, and/or altering itsinterface materials such that the speed of sound and/or light is changedin them so that the fields that impinge on the tissue to be stimulatedare tuned to the nerve cells targeted, and/or altering the dispersiveproperties of its interface materials so the mechanical and/orelectrical fields have a controllable frequency dependent behavior inthe materials such as to tune the field frequencies to neural effect,and/or making its interface materials capable of filtering the fields asto tune the fields to neural effect, and/or altering the densities ofthe interface materials altering the transmission of fields through theinterface to maximize neural effect, and/or allowing its interfacematerials to shift the phase of individual fields thereby restructuringthe waveforms that impinge on the neural tissue, and/or altering thefocus or targeting of the fields to stimulate different neural targets,and/or altering the orientation of the vector field components therebypotentially altering the neural response of the stimulated cell (forexample inhibiting or facilitating the cells based on the finalstimulating current density orientation relative to the neural body-axonaxis), and/or altering the magnitude of the fields to maximize neuraleffect, and/or altering the field waveform dynamics/shapes to tuneneural response, etc.

While a mechanical source 16 can be used and applied to the scalpthrough the interface mechanism in this exemplary embodiment, many othermeans could be applied to alter the electromagnetic properties of theunderlying tissue, and similar property matching and/or coupling couldbe enacted across all of the different mechanisms for altering theelectromagnetic properties of the tissue (including thermal, chemical,optical, electromagnetic, and/or mechanical properties) to generate thedesired current for stimulation based on matching and/or coupling thesource(s), field(s), and/or agent(s) and/or tissue properties throughthe interface.

It is further envisioned that the interface component may be comprisedof one or separate pieces and serve only to couple the mechanical fieldwith the underlying tissue or the electrical field with the underlyingtissue separately (or they may be designed so that they are separate butintegrateable (or just used with separate non-housed electrical and/ormechanical sources)). The interface component(s) could also be designedto couple the electromagnetic and mechanical fields before being focusedon the tissues, such as for example in an appropriate housing paradigm(potentially including the proper placement of the primary electricfield source and the means for altering the electromagnetic tissueproperties) whereby the fields are coupled appropriately before beingfocused on the tissues (or to facilitate the subsequent focusing on orinto the tissues). The interface component(s) itself can be adjustablein shape, size and/or position, and/or allow for the movement and/orreshaping and/or resizing of the parts that are embedded within it orattached on it such that either of the sources (electrical and/or meansfor altering tissue characteristics) can be adjusted relative to thetissue to be stimulated (such as for example allowing movement of theelectric field source or mechanical field source relative to the tissueas might be used for adjustable targeting of locations to bestimulated).

The interface apparatus(s) may have its number of uses controlled(and/or control the duration of a stimulation session(s)). This controlcould be used to increase the efficiency of its application or to avoidoveruse. Examples in which uses could be controlled includeincorporating an integrated electrical circuit which can control thenumber of uses (and/or stimulation session durations) through which thecomponent may be used; using interface creams, fluids, materials,pastes, and/or gels which can be fashioned to be only functional for asingle use (or a controlled number of uses and/or stimulation sessionduration); incorporating mechanical safety latches which deactivate theitem after a single use (or a controlled number of uses and/orstimulation session duration); using a composite material which makes uppart of the interface apparatus and can regulate the number ofapplications (and/or stimulation session duration); and/or otherstandard mechanisms (all used individually or in any combination).Additionally, the interface component(s) may be reusable, where theelectrodes (i.e., electrical source components) and/or means foraltering the tissue electromagnetic properties (i.e.,ultrasound/mechanical, chemical, thermal, optical, and/or secondaryelectromagnetic source(s)) are removable and/or replaceable within theinterface component and/or made of materials such that they aremulti-use.

Other embodiments can incorporate item such as a separate piece(s) thatare wearable component(s) for any other body part including and beyondthe head/scalp as mentioned above (such as a back brace like wearableitems for spinal cord stimulation, a knee brace like component, etc), anexternal wrap(s) (of various shapes tailored for any part of the body),materials that can be worn separately and integrated into other wearableitems, bridging blocks, electrode like components, a physical boundarycomponent of the headpiece of a transducer mechanism for the primaryelectromagnetic field source and/or the means to modify theelectromagnetic tissues parameters (that may serve as a medical deviceinterface where the type of mechanism that facilitates the coupling ofthe fields could be used for a headpiece of a transducer of a medicaldevice for applying the appropriate fields and/or additional means foraltering the tissue electromagnetic parameters—this headpiece could forinstance be integrated into chair type device that one might sit in forstimulation), and/or any combination of the above. Also, the differentcomponents could be made from multiple separate pieces, that may beintegrateable or separately functioning, such as for a cap likemechanism there could be one cap mechanism that serves to hold theelectrical field source electrodes and a separate cap holding theultrasound source (or sources of mechanical fields, chemical agents,thermal fields, optical fields/beams, and/or secondary electromagneticfields), both made of materials to facilitate the transmission of thegiven fields and/or agents.

It is also envisioned that the interface component may be housing formaterials, such as fluid(s) and/or gel(s), through which the mechanicalenergy and/or electrical energy transmits and/or materials at thetransducer and/or electrode interface through which either or bothfields transmit with underlying subject to be stimulated (for example anultrasonic gel which also allows the conduction of electricalfields/currents). Thus, the interface component does not have todirectly house either the electrical source or a means for altering theelectromagnetic properties of tissue, but it can serve as an interfacebetween tissues and an external electrical source and/or an externalmeans for altering electromagnetic tissue properties which are adjacentto the interface (which could be matched and/or coupled in some way tothe tissue to be stimulated (and/or to each other) through the interfaceapparatus). Thus, the interface apparatus could have neither the primaryelectric source nor the means to alter the electromagnetic properties ofthe tissue directly embedded within or attached to it, but could justserve to match and/or couple the properties of at least one of thecomponents (together or individually and separately) and/or thetissue(s) to be stimulated through the proper matching and/or couplingof its material properties, inert and/or active, as exemplified above.

The interface component could also be implemented to augment stimulationin other ways. For example, the interface could be used to cool thetissue in the regions of the interface, for example if placed on thescalp the interface itself could maintain fluid which couples anultrasound source to the scalp, but could be cooled at the same timesuch that the scalp and underlying skull itself do not heat due toultrasound applications. Further, the nearby neural tissue can be cooledsuch that its metabolism is slowed at the surface allowing potentiallymore focal stimulation below (or to enact controlled stimulation atdifferent regions of depth (for example where deeper tissues might notbe cooled as much as the tissues proximal to the fluids, but in a way tohelp control the effects of neural stimulation)). Additionally, suchcooling could be used to further alter the electromagnetic properties ofthe tissues.

For all of the different combinations of means for altering theelectromagnetic properties of the tissue and the primary electromagneticsource, the different source components (i.e., primary electrical sourceand/or mechanical, chemical, thermal, optical, and/or secondaryelectromagnetic source) can also be designed to allow the transmissionof the fields (or agents, etc.) through each component if placed in sucha way to be in one or another's transmission paths (an example of onesuch permutation is provided in the bridging block example of FIG. 2),where an externally applied ultrasound field can transmit through theprimary electrical field source. On such example could be an apparatuswhere the electric field source could be designed of the appropriateacoustic properties such that it does not interfere with thetransmission of the ultrasound field to the underlying tissues, or theelectric field and mechanical field source are the same element(s)). Itis envisioned that any permutation of placements is possible.

As previously mentioned, the means for altering the electromagneticcharacteristics of tissue may be substituted or combined with anycombination of mechanical fields, chemical agents, thermal fields,optical fields/beams, and/or secondary electromagnetic fields. Thematerials or properties of the interface component can be matched and/orcoupled with the different sources and/or the primary electric fieldand/or the means to alter the tissue electromagnetic properties(source(s), field(s), and/or agent(s)) and/or the tissue to facilitatethe current alteration process (with interface materials that are activeand/or inert).

Thus, the interface apparatus according to the present disclosure couldinclude a chemical source to alter at least one electromagneticcharacteristic of the tissue(s) to be stimulated. In such a situation,it is envisioned that the interface component would comprise materialshaving appropriate properties such that a chemical reaction and/or atransmission of chemical agents between tissue and the chemical sourceis facilitated thereby creating an interface in part between tissue andthe chemical source. It is also contemplated that an optical source canbe used to alter at least one electromagnetic characteristics of tissueto be stimulated. The interface component could include materials havingappropriate optical parameters such that the optical properties of thetissue(s), source(s), field(s), and/or the interface are matched and/orcoupled thereby creating an interface in part between tissue and theoptical source. Similarly, the means for altering at least oneelectromagnetic tissue characteristic of tissue(s) to be stimulatedcould be a thermal source. The interface component could includematerials having appropriate thermodynamic parameters such that thethermodynamic properties of the tissue(s), source(s), field(s), and/orthe interface are matched and/or coupled thereby creating an interfacein part between tissue and the thermal source. Further, a secondaryelectromagnetic source could be used and the interface component couldincorporate materials having appropriate electromagnetic parameters suchthat the electromagnetic characteristics betweens the tissue(s),source(s), field(s), and/or the interface are matched and/or coupledthereby creating an interface in part between said region of tissue andthe electromagnetic source. And, the interface apparatus according tothe present disclosure could include a mechanical (acoustic) source toalter at least one electromagnetic characteristic of the tissue(s) to bestimulated. In such a situation, it is envisioned that the interfacecomponent would comprise materials having appropriate mechanical(acoustic) properties such that the mechanical (acoustic)characteristics betweens the tissue(s), source(s), field(s), and/or theinterface are matched and/or coupled thereby creating an interface inpart between said region of tissue and the mechanical (acoustic) source.This concept of matching the properties may be applied in anypermutation (via the interface and/or the tissues and/or with anypotential sources, including the primary electrical source(s) and/orfield and/or any means for altering the tissue electromagneticproperties (i.e., the ultrasound/mechanical field and/or source(s),chemical agent and/or source(s), thermal field and/or source(s), opticalfield/beam and/or source(s), and/or secondary electromagnetic fieldand/or source(s))).

FIG. 2, demonstrates an exemplary embodiment of the interface apparatusaccording to the present disclosure. For example, interface apparatus 8illustrated in FIG. 2 according to the present disclosure may be appliedto the area of neural stimulation (and in particular brain stimulation)and can serve as a bridging block interface mechanism between thesources and the tissue to be stimulated. An electrode 12, as an electricsource, is applied to the scalp through the interface component 10, inwhich the electrode can be attached to, embedded in, placed on top of,or fastened within (or any combination to) the interface mechanism. Theelectrode 12 could be such that it is in direct contact with the tissuebelow, embedded within the material where it is not in direct contactwith the tissue below, or just an electrically conducting material (suchas a paste, gel, and/or fluid in contact with a current and/or voltagesource) that is adjacent to or connected to the surface of the interfaceapparatus.

As depicted in FIG. 2, a second free electrode 15 is attached on theindividual to be stimulated, at any location, such as within the mouth(also as an electric source). An electric field 14 is generated betweenthe electrodes. A free standing mechanical source 16 (the mechanicalsource may be, for example, any acoustic source such as an ultrasounddevice) is applied to the scalp via the interface component 10 andprovides concentrated acoustic energy 18, (i.e., mechanical field) to afocused region of neural tissue, affecting a smaller number of neurons22 than affected by the electric field 14, by the mechanical field 18altering the tissue electromagnetic characteristics relative to theapplied electric field 14, and thereby generating the altered current24. Both the electrode 12, and the material, inert and/or active, of theinterface component 10 can be designed such that they are acousticallymatched and/or coupled with the mechanical field 18 that transmitsthrough them (for example, one could use the matching and/or coupling tolimit the attenuation and/or modification (i.e., dispersion effects,phase shifting, beam focus, etc) of the mechanical field), and/or toalter the mechanical fields properties such as to be ideal forstimulation, for example through matching the acoustic impedances of thesources with the material of the bridging interface and/or the tissues.The interface could also have its electromagnetic properties matchedand/or altered relative to the electrical source (and/or the tissuesand/or the material of the interface bridging block) to facilitate thecurrent alteration (such as by matching all of the electric impedancesof the relevant parts through the appropriately designed interface). Onecould envision the interface component 10 could be filled with a fluidthrough which the mechanical field 18 can travel unimpeded where theelectrode 12 is an electrically conducting thin latex like membrane(connected to a voltage or current source) that is coated in aconducting ultrasound gel at the tissue-interface boundary through whichthe ultrasound energy can transmit. The fluid above the membrane couldbe non-conducting such as to prevent the spread of the electric fieldinto the fluid (such that electrical energy focused towards theunderlying tissue does not spread to the fluid above contained withinthe interface component). This concept of matching the properties may beapplied in any permutation (via the interface and/or the tissues and/orwith any potential sources, including the primary electrical source(s)and/or any means for altering the tissue electromagnetic properties(i.e., the ultrasound/mechanical field and/or source(s), chemical agentand/or source(s), thermal field and/or source(s), optical field/beamand/or source(s), and/or secondary electromagnetic field and/orsource(s))).

Additionally, neither the electrode 12, nor the mechanical source needto be contained within the interface component, but for example in asituation where both are free standing, the interface component could bedesigned to couple the field(s) transmitted through it to the tissuebelow (through the appropriate acoustic and electric matching and/orcoupling of the interface component and the tissues below (i.e., themechanical and electrical source make contact with the interfacemechanism at its boundary)). For example, the interface component 10,could be filled and/or coated with fluid(s) (such as degassed water)and/or gel(s) (such as ultrasound coupling gel) which in part serves tocouple the mechanical/ultrasound source with the tissue and/or befabricated of electrically conducting material which focuses an appliedelectrical field.

Additionally, the order in which the primary electrode 12 and mechanicalsource 16 are applied relative to the tissue and interface component 10need not be fixed, the sources can be designed such that one field couldtransmit through the other source (or placed such that they do notinterfere with each others' transmission (i.e., just through relativepositioning), or even with a region of one removed so that thetransmission path of the other is not crossed, in part or full, and/orsuch the mechanical and electrical field are generated from the samecomponent). Additionally, the interlace component 10 can have ports thatcan be used to bring materials/fluids in and/or out (and/or on and/oroff) of the interface apparatus 8 (such as for example with a coolingfluid, to circulate degassed water through the apparatus, an electricalconducting gel/fluid, etc).

FIG. 3, depicts another exemplary embodiment of the interface apparatusaccording to the present disclosure. The interface apparatus 8illustrated in FIG. 3 may be applied to the area of neural stimulation.Interface component 10 can be a headpiece of a medical device betweenthe sources and the tissue to be stimulated. An electrode 12 is appliedto the tissue through the interface component 10. A second freeelectrode 15, also as an electric source, is attached on the tissue tobe stimulated (or, at any location of proximal tissue); as with all theembodiments above, clearly a monopolar or multipolar electrode scheme isalso possible. An electric field 14 is generated between the electrodes(or from a monopolar electrode where the second free electrode would notbe used, or between multiple electrodes where a multipolar scheme isused). The same component that serves as an electrical source 12 canserve as the mechanical source (i.e., the mechanical source may be anyacoustic source such as an ultrasound device, such that the ultrasoundtransducer face could also be composed of materials that could serve asthe electric field source—such as for example placing the entire face ofthe transducer(s) at a voltage relative to the tissue) or the mechanicalsource could be a separate piece entirely, as in the previous figures.The electrical/mechanical source is applied to the tissue and providesconcentrated acoustic energy 18, (i.e., mechanical field) to a focusedregion of neural tissue, affecting a smaller number of neurons 22 thanaffected by the electric field 14, by the mechanical field 18 alteringthe tissue electromagnetic characteristics relative to the appliedelectric field 14, and thereby generating the altered current 24. Theapparatus can be connected to the underlying tissue(s) via fluids, gels,creams, pastes, and/or any appropriate material whereby the material maycoat the entire apparatus, be at the apparatus-tissues(s) interface, becontained within the apparatus, and/or be injected into the path to thetargeted area (from either an external material source and/or anintegrated material chamber housed in the apparatus).

Another embodiment disclosed herein based on this principles elaboratedon throughout could be a tDCS electrode cap which is similar to theabove interface apparatus, with the means for altering theelectromagnetic properties of the tissues to be stimulated removed. Theelectrodes could be placed for functional targeting based on a subject'sspecific condition or anatomy. It could also be based on dry electrodes,which would not leave debris from stimulation on the subject (or basedon whatever means was acceptable for medically fixing the electrodes/orbridging the electrical fields to the individual's scalp and underlyingtissues).

And furthermore, the interface component(s) in conjunction with thealtered current generation could similarly be applied in the areas ofaltering cellular metabolism, physical therapy, drug delivery, and genetherapy as explained in the referenced patent application (U.S. patentapplication Ser. No. 11/764,468, Apparatus and Method for Stimulation ofBiological Tissue) and above. These examples are provided not to beexhaustive, but as an example of potential applications.

As should be noted by one skilled in the art, throughout this entiredisclosure, the reference to tissue can serve to mean tissue overlyingthe final stimulated tissue and all or some of the subsequent underlyingor proximal tissue to be targeted for stimulation (i.e., where fieldsmight be transmitted through multiple tissues before being focused ontheir final tissue focus—such as for example, through the skin, skull,CSF, gray matter, and white matter to be focused on underlying graymatter nuclei during stimulation of deep gray matter nuclei in the brain(i.e., tissue would refer to all of the tissues in the path of thestimulation field(s) and/or agents)). Further, the different sources(i.e., primary electrical source and means for altering the tissueelectromagnetic properties) can be combined as single units.Additionally, the term material is not meant to be exclusive, but torefer to both active and/or inert materials throughout the document.

In accordance with the present disclosure, the embodiments disclosedherein may be used with a process that stimulates tissues through thecombined application of electrical and mechanical fields (and/orchemical agents, thermal fields, optical fields/beams, and/or secondaryelectromagnetic fields) for the perturbation and/or modification oftissue permittivity and/or tissue conductivity for the generation of anew and/or altered displacement currents and/or ohmic currents, thegeneration of a new electric field with corresponding new ohmic anddisplacement current components (generated due to the tissueperturbation relative to the applied electric field), and/any currentsthat result due to continuity conditions with altered currents from thetissue electromagnetic property perturbation, and/or any combinationthereof for stimulation.

While the inventions within this disclosure have been illustrated anddescribed in detail in the drawings and/or foregoing description, thesame is to be considered as illustrative and not restrictive incharacter, it being understood that embodiments have been shown anddescribed and that all changes and modifications that come within thespirit of these inventions are desired to be protected.

1-16. (canceled)
 17. A stimulation apparatus comprising: a capconfigured to interact with a head of a user; a first energy sourcecoupled to the cap, the first energy source configured to emit a firstenergy field to a region of tissue; and a second energy source coupledto the cap, the second energy source configured to emit a second energyfield to at least a portion of the region of tissue; wherein the capfurther comprises a material that acts as a bridging medium between theregion of tissue and the first source and/or the second energy source,and the cap is configured such that a portion of the second energy fieldemitted by the second energy source intersects a portion of the firstenergy field emitted by the first energy source in the region of tissue.18. The apparatus according to claim 17, wherein the first energy sourceis embedded in the cap.
 19. The apparatus according to claim 17, whereinthe first energy source is fastened to the cap.
 20. The apparatusaccording to claim 17, wherein the first energy source is placed on asurface of to the cap.
 21. The apparatus according to claim 17, whereinthe second energy source is embedded in the cap.
 22. The apparatusaccording to claim 17, wherein the second energy source is fastened tothe cap.
 23. The apparatus according to claim 17, wherein the secondenergy source is placed on a surface of to the cap.
 24. The apparatusaccording to claim 17, wherein the first energy source and the secondenergy source are adjustably coupled to the cap relative to the tissue.25. The apparatus according to claim 17, further comprising a controlelement.
 26. The apparatus according to claim 25, wherein the controlelement controls a feature selected from the group consisting of: numberof uses and number of stimulations per session.
 27. The apparatusaccording to claim 17, wherein the apparatus comprises multipleremovable parts.
 28. The apparatus according to claim 27, wherein atleast one of the parts is disposable.
 29. The apparatus according toclaim 17, wherein the material is a fluid or gel.
 30. The apparatusaccording to claim 17, wherein the first energy source is an electricenergy source.
 31. The apparatus according to claim 30, wherein theelectric energy source is an inductive electric energy source.
 32. Theapparatus according to claim 17, wherein the second energy source is anultrasound device.
 33. The apparatus according to claim 17, furthercomprising circuitry operably coupled to the cap and operably connectedto the first and second energy sources, the circuitry being configuredto be responsive to a telecommunication device.
 34. The apparatusaccording to claim 17, wherein the cap is adjustable.